CO2 ionic trapping at meta-sedimentary aquifer, following a CO2 injection push-pull test

In order to study CO2-water-rock reactions relative to effectiveness of CO2 geological storage, small-scale CO2 injection experiments were performed, as single well push-pull tests, at the Lamont Doherty Earth Observatory test well site (New-York, USA). The injection interval was located at the contact zone between the chilled dolerite and the underlying metamorphosed sedimentary rocks. The variations of post-injection chemical and isotopic characteristics of retrieved water samples (major ions, DIC, 13CDIC) underline the CO2 reactivity in the aquifer and allow to identify reactions of the dissolved CO2 with the surrounding rocks, mainly the dissolution of carbonate minerals and complementary cation exchange.